Cycling Question

[sbga]

I recently got a 10 gallon tank to set up as a quarantine/treatment tank. My regular tank is a 20 gallon with over-the-back filter and undergravel pump.
I am using the over-the-back filter from the 20 gallon in the new 10gallon quarantine tank so it cycles faster or maybe it won't have to cycle at all since the filter probably has a lot of beneficial bacteria
I dont think it should cause the 20 gallon to go through a cycle because there is probably plenty of bacteria in the rocks because it has an undergravel pump also.

Does anybody think this will work? If so, how long until I will be able to transfer my sick fish to the quarantine tank without having to worry about them going through a cycle?

 

[Bignose]

I don't think that this will work at all. While there are bacteria on every surface of the tank, a significant majority of all the bacteria still live in the filter. Think about it from a bacteria pint of view -- the food is brought right to you. Because of the pump and the splashing from the filter return, the water that comes into the filter is highly oxygenated. And the there is lots of surface area to live on. The filter is a bacterium's dream home.

The tank with the filter will be cycled, and the tank without the filter will not be. You can't have both cycled with your present situation.

If you need the quarantine tank immediately, just be prepared to do water changes every day -- that will help keep the pollution levels way down. Besides, a lot of the medicines used to treat fish kill off beneficial bacteria anyway -- depending on what you are treating for, it may be impossible to cycle anyway!

For future planning, keep the filter you have running now on the 20 gal. And, then, buy a second filter, and also run it on your 20 gal tank. Then, next time you need a quarantine tank, you can take one of the filters off the main tank and use it in the q-tank. That way, both tanks will be close to being cycled (each filter will hold about half of the total bacteria). When you clone a bacterial colony like that, it usually is less than a day until the tank is fully cycled again (filter bacteria double in number roughly every 24 hours).

 

[sbga]

Maybe I was a little unclear. The 20 gallon has been set up for over 5 years and I'm sure the bacteria is thriving in the HOB filter and in the gravel. Your argument makes no sense to me. I am simply taking the HOB from the estabilished tank (which BTW also has a undergravel filter so this wont effect it), and putting it on the new 10g tank. I am taking the un-estabilished HOB that came with the new 10 gallon and putting it with my 20 gallon tank so it will begin the gain bacteria. I have not used any medication yet and don't plan to do so for a while

 

[OldMan47]

If you are just trying to get the filter ready for future use, why not put it on the 20 like bignose suggested? That way your 20 will never see a cycle and when you need the QT it will have a cycled filter ready to go.

 

[sbga]

Because the 20 is a hex and there's not enough room to put 2 filters unless I take the hood off. Plus I need the quarantine tank now because I have a couple sick fish

 

[rdd1952]

You are running a HOB and a UGF on that tank. Depending on which one has the stronger flow rate (my guess would be the HOB), that is the one that will house the most bacteria as there is more food passing through it. It's possible that there is very little bacteria in the gravel as you always get tunneling in the gravel as it gets plugged thus slowing the flow rate.

My suggestion would be to just take some filter media from the 20 gallon HOB and add it to the filter for the 10 gallon. If you are only going to put one fish in there, you don't need a lot of bacteria. And depending on what you will be medicating with, it could kill of the bacteria anyway.

 

[Bignose]

A HOB versus a UGF is almost no contest. A UGF may actually move more water, just more slowly, but the other variable of oxygen content won't even be close. A HOB normally takes back in somewhere are 50% of the water it just returned to the tank -- simply because most filters' return and intake a very close to each other. That returned water is going to have very close to the maximum amount of oxygen possible. Comparatively, the amount of oxygen at the bottom of the tank is going to be low -- the bacteria are going to preferentially congregate where conditions are best and that is the HOB filter. Like I said, it isn't even going to be close -- the vast majority of the number of bacteria are going to be in the HOB filter.

If you take the HOB filter away, there will be a mini cycle. Depending on the splits in the numbers, maybe even a major cycle.

This may all be moot anyway... what do you think your fish have and what do you plan on treating them with? If you are going to be treating with some strong chemicals, the q-tank may not even be able to support bacteria...